Disable xdebug on travis to speed up builds

see https://twitter.com/AdrienBrault/status/525695269979975680
Merge pull request #20 from mathroc/feature/faster-travis

Disable xdebug on travis to speed up builds
Remove unused file
Fix merge "imports" config recursively
Merge pull request #22 from mathroc/feature/cleaning

Remove unused file
Setup Whoops to handle error & exception to improve DX
Merge pull request #24 from mathroc/fix/config-merging

Fix merge "imports" config recursively
Merge pull request #25 from mathroc/dx/whoops

Setup Whoops to handle error & exception to improve DX
OAuth2